1. Technical Field
The present invention pertains to an optical recording method, an optical reproducing method, and an optical reproducing apparatus, and particularly relates to an optical recording method that uses the same lens for a Fourier transformed signal beam, which represents binary digital data with a brightness image, and a reference beam. The method simultaneously irradiates the Fourier transformed signal beam and reference beam onto an optical recording medium for recording the signal beam as a hologram. The present invention also pertains to an optical reproducing method and apparatus that reproduce the binary digital data carried by the signal beam from the optical recording medium on which the hologram is recorded by this optical recording method.
2. Related Art
With holographic data storage, the “0,1” of binary digital data is changed into a digital image (a signal beam) as a brightness image, and the signal beam is Fourier transformed by a lens and irradiated onto an optical recording medium. At the optical recording medium, the Fourier transformed image is recorded as a hologram.
For such recording, a coaxial hologram recording system which causes the signal beam and the reference beam to enter the same lens, and causes both Fourier transformed patterns to interfere with each other in the optical recording medium for recording the hologram is proposed.